The present invention generally relates to the field of mixing colors of light and, more up particularly to a device/method that is able to sufficiently mix different colors of light over a relatively short distance between a light entry surface and a light exit surface.
Various types of light indicators are used in many types of computer hardware, such as disk drives, servers, printers and the like. In many of these applications an amber light is produced by introducing both a red light source and a yellow light source into a relatively long and tortuous optical path. Although this may be acceptable in many situations, certain system configurations have insufficient space to accommodate this type of light mixing technique.
The present invention generally relates to mixing light from different light sources into a single color of light. The present invention is embodied in a color mixing device that includes a mixer that in turn has an aperture. Light from at least two light sources (e.g., light of different wavelengths) each introduce light into the mixer along a path such that at least a portion of this light is at least generally directed toward a surface of the mixer that defines this aperture. Mixing of the light from the multiple light sources into a single color is accomplished by the multiple reflections that occur between that surface of the mixer that defines the aperture and exterior surfaces of the mixer.
Various refinements exist of the features noted in relation to the present invention. Further features may also be incorporated in the present invention as well. These refinements and additional features may exist individually or in any combination. The mixer may be formed from a plastic material, such as polycarbonate, glass, or any other appropriate light-transmitting material. The mixer may also be in the form of a solid body. Multiple particles may be embedded throughout this body. Enhancement of the mixing of the light from the multiple light sources is believed to be realized through the addition of these particles throughout the body of the mixer, particularly in the case where these particles are metal particles or formed from other reflective materials. Bubbles may also be encapsulated within this body to promote mixing as well. A combination of bubbles and particles of reflective material could also be utilized. Preferably, the noted aperture extends entirely through the body of the mixer.
The mixer may be characterized as having a light entry surface, namely that surface where light from the multiple sources is initially introduced into the mixer. The distance between the light entry surface and the aperture of the mixer may have an effect on the extent to which the light from the multiple light sources is mixed within the mixer. Preferably this distance is sufficiently small to encourage multiple reflections between the light entry surface and that surface of the mixer which defines the aperture. However, the distance between the light entry surface and the aperture must be sufficiently large so as to allow for sufficient transmission of light to that surface of the mixer which defines the aperture for reflection to even occur. In one embodiment, the distance between the light entry surface and that portion of the aperture which is closest to the light entry surface is within a range of about 5 mm to about 10 mm, and in another embodiment is no more about 1 mm.
The mixer may also be characterized as having a light entry surface where light is initially introduced into the mixer, and further as having a light exit surface where light exits the mixer. In one embodiment, the light entry surface is smooth and the light exit surface is in a roughened condition. Roughening of the light exit surface is believed to enhance the mixing of the light within the mixer. All exterior surfaces of the mixer in this particular embodiment, except the light entry surface, may be roughened to further promote sufficient mixing of the light. Preferably, the surface roughness of the xe2x80x9croughenedxe2x80x9d surfaces of the mixer in this case is at least about xe2x80x9cMold-Techxe2x80x9d standard MT-11040. In another embodiment, the light entry surface and the light exit surface both have a surface roughness of at least about xe2x80x9cMold-Techxe2x80x9d standard MT-11040.
The light entry and exit surfaces also may be characterized as being disposed on opposite sides of the aperture. In this case, the longitudinal extent of the first aperture may be disposed at least generally parallel to one or both of the light entry and exit surfaces. Furthermore and for the case where the light entry and exit surfaces are disposed on opposite sides of the noted aperture, the overall distance therebetween may be relatively small to allow the present invention to be used where space constraints exist. In one embodiment, the light entry and exit surfaces are separated by a distance of no more than about 12 mm, although other relative spacings may be utilized where space constraints are not an issue.